accepts united healthcare benefit plans. find a clinic near you at minuteclinic.com. >>> jumping off of a bridge a building or a cliff is one of the most dangerous sports there is and that's why this man wants to do it. starting to become more mainstream in the sport of tandem jumping. a new way of risking your neck. >> 2012 becomewelcome. who's ready to do base jumping? >> reporter: one saturday every fall the new river gorge bridge in fayetteville west virginia transforms into a human launch pad. it's known as bridge day. the largest event in the world dedicated to a sport that defines the word "extreme." >> bridge day is not safe. basically the best way to describe it. that's what makes it so cool. 450 jumpers from 41 states and 10 countries. an amazing event. >> reporter: it's illegal in most of country. a free-fall parachuted jump off a fixed object. the jump must be from antenna, span from the earth itself. the length of free fall make it the dangerous younger cousin to skydiving. mark kittner has been jumping out of p